健脾消癌方通过PI3K/Akt信号通路抑制结肠癌血管生成的研究＊

目的 观察结肠癌HCT116细胞健脾消癌方的条件培养液对HUVEC细胞管腔形成的影响，从PI3K/Akt生物轴调控角度探讨其作用机制。方法 培养HCT116细胞，细胞设3组：对照组，健脾消癌方组（加入15%健脾消癌方含药血清）及人参皂苷Rg3组；制备HCT116细胞健脾消癌方条件培养液（分组及制备方法见实验方法），用条件培养液干预HUVEC（脐静脉内皮细胞，Human Umbilical Vein Endothelial Cells），Matrigel基质胶法检测HCT116细胞健脾消癌方条件培养液对HUVEC小管形成的影响。随后采用蛋白免疫印迹法（Western blot）检测各组HCT116细胞磷脂酰肌醇3-激酶（PI3K）、蛋白激酶B（Akt）、p-Akt、VEGF（血管内皮生长因子，Vascular endothelial growth factor）蛋白表达。最后在结肠癌HCT116荷瘤小鼠中验证健脾消癌方对肿瘤生长速度的影响，并经瘤组织VEGF蛋白表达、CD31免疫组化染色检测肿瘤内血管生成情况。结果 模型组HUVEC细胞管腔形成较空白血清组显著增加（P<0.05）；健脾消癌方组及人参皂苷Rg3组较模型组HUVEC细胞管腔形成显著减少（P<0.01）。p-Akt和VEGF蛋白表达水平模型组高于空白血清组（P<0.05），健脾消癌方组及人参皂苷Rg3组显著低于模型组（P<0.01）；PI3K、Akt蛋白表达量组间差异无统计学意义。与对照组比较，模型组荷瘤小鼠肿瘤体积显著性增大，瘤组织内VEGF表达、CD31阳性面积显著性增加，差异有统计学意义（P<0.05）；与模型组比较，健脾消癌方组及人参皂苷Rg3组荷瘤小鼠肿瘤体积显著减小，瘤组织内VEGF表达、CD31阳性面积降低，差异有统计学意义（P<0.05）。结论 健脾消癌方可抑制肿瘤的血管生成和生长，其作用机制可能与PI3K/Akt生物轴调控VEGF表达有关。     

沉默TRIM23基因抑制骨肉瘤细胞的增殖

目的 探讨TRIM23基因对骨肉瘤细胞增殖能力的影响.方法 应用Western blot实验检测TRIM23基因在骨肉瘤细胞中的表达;应用shRNA质粒转染骨肉瘤细胞系U2OS,通过MTT与平板克隆形成实验评估细胞增殖能力;应用Westernblot实验检测U2OS细胞Akt/P53/P21通路的表达改变.结果 TRIM23蛋白在骨肉瘤细胞中的表达高于成骨细胞;沉默TRIM23基因可以抑制骨肉瘤细胞的增殖能力;沉默TRIM23基因下调P-Akt表达,但总Akt的表达无明显改变,上调P53与P21的表达.结论 TRIM23在骨肉瘤细胞中表达升高,TRIM23能通过调节Akt/P53/P21通路影响骨肉瘤细胞的增殖.     

The NEDD4-1 E3 ubiquitin ligase: A potential molecular target for bortezomib sensitivity in multiple myeloma

E3 ubiquitin ligases primarily determine the substrate specificity of the ubiquitin-proteasome system and play an essential role in the resistance to bortezomib in multiple myeloma (MM). Neural precursor cell-expressed developmentally downregulated gene 4-1 (NEDD4-1, also known as NEDD4) is a founding member of the NEDD4 family of E3 ligases and is involved in the proliferation, migration, invasion and drug sensitivity of cancer cells. In the present study, we investigated the role of NEDD4-1 in MM cells and explored its underlying mechanism. Clinically, low NEDD4-1 expression has been linked to poor prognosis in patients with MM. Functionally, NEDD4-1 knockdown (KD) resulted in bortezomib resistance in MM cells in vitro and in vivo. The overexpression (OE) of NEDD4-1, but not an enzyme-dead NEDD4-1-C867S mutant, had the opposite effect. Furthermore, the overexpression of NEDD4-1 in NEDD4-1 KD cells resensitized the cells to bortezomib in an add-back rescue experiment. Mechanistically, pAkt-Ser473 levels and Akt signaling were elevated and decreased by NEDD4-1 KD and OE, respectively. NEDD4-1 ubiquitinated Akt and targeted pAkt-Ser473 for proteasomal degradation. More importantly, the NEDD4-1 KD-induced upregulation of Akt expression sensitized MM cells to growth inhibition after treatment with an Akt inhibitor. Collectively, our results suggest that high NEDD4-1 levels may be a potential new therapeutic target in MM.     

LncRNA MEG3靶向miR-181a-5p调控宫颈癌细胞放射敏感性

目的 研究LncRNA MEG3对宫颈癌细胞放射敏感性的影响,并探讨其作用机制。方法 运用qRT-PCR法检测放射抗性和放射敏感性宫颈癌细胞中LncRNA MEG3的表达;将过表达对照组(转染pcDNA 3.1)、过表达LncRNA MEG3组(转染pcDNA 3.1-LncRNA MEG3)、抑制miR-NC组(转染anti-miR-NC)、抑制miR-181a-5p组(转染anti-miR-181a-5p)、过表达LncRNA MEG3+过表达miR-NC组(共转染pcDNA 3.1-LncRNA MEG3和anti-miR-NC)、过表达LncRNA MEG3+过表达miR-181a-5p组(共转染pcDNA 3.1-LncRNA MEG3和anti-miR-181a-5p),均用脂质体法转染至SiHa细胞;克隆形成实验检测细胞的存活分数;流式细胞术检测细胞的凋亡率;双荧光素酶报告基因检测实验检测细胞的荧光活性;Western blot检测细胞中PTEN、p-Akt、Akt的蛋白表达。结果 与放射敏感组相比,放射抗性宫颈癌组织中LncRNA MEG3的表达明显降低(P<0.05),其表达量与宫颈癌细胞的放射敏感性呈正相关;过表达LncRNA MEG3、抑制miR-181a-5p均可显著增强宫颈癌细胞SiHa放射敏感性,促进凋亡(P<0.05);野生型LncRNA MEG3细胞的荧光活性受miR-181a-5p的抑制。过表达miR-181a-5p逆转了LncRNA MEG3对宫颈癌细胞放射增敏和促凋亡作用及对PTEN/Akt信号通路的调控。结论 长链非编码RNA LncRNA MEG3可增强宫颈癌细胞放射敏感性,其机制可能与靶向miR-181a-5p调控PTEN/Akt 信号通路有关,可为提高宫颈癌的预后提供新方向。     

穴位埋线对肾虚血瘀型子宫内膜异位症患者IL-1β、TNF-α、VEGF和MMP-2水平的影响

目的:基于PI3K/Akt/mTOR信号通路,探讨穴位埋线疗法治疗肾虚血瘀型子宫内膜异位症的临床疗效及对IL-1β、TNF-α、VEGF和MMP-2等相关信号通路下游细胞因子的水平的影响。方法:选取肾虚血瘀型子宫内膜异位症的门诊和住院患者86例,按照随机数字表法随机分为穴位埋线组和西药组,西药组口服孕三烯酮胶囊(内美通),穴位埋线组在西药组的基础上采用穴位埋线进行治疗,治疗3个月后观察两组患者的临床疗效和IL-1β、TNF-α、VEGF、MMP-2等相关信号通路下游细胞因子的水平。结果:治疗后穴位埋线组总有效率93.02%(40/43),西药组总有效率83.72%(36/43),两组比较差异无统计学意义(P>0.05)。治疗3个月后,穴位埋线组和西药组的VAS评分、血清IL-1β、TNF-α、VEGF和MMP-2水平均较治疗前改善(P<0.01),但穴位埋线组较西药组改善更为明显(P<0.05或P<0.01)。治疗过程中,西药组不良反应发生率为18.60%(8/43),穴位埋线组不良反应发生率为4.65%(2/43),两组不良反应发生率比较,差异有统计学意义(P<0.05)。结论:穴位埋线可以显著改善子宫内膜异位症患者的临床症状和体征,并能显著降低孕三烯引起的不良反应,可见穴位埋线疗法可以作用PI3K/Akt/mTOR信号通路,通过改善通路下游的IL-1β、TNF-α、VEGF和MMP-2水平,发挥治疗子宫内膜异位症的作用。     

PRKAA1 Promotes Proliferation and Inhibits Apoptosis of Gastric Cancer Cells Through Activating JNK1 and Akt Pathways

PRKAA1 (protein kinase AMP-activated catalytic subunit 1) is a catalytic subunit of AMP-activated protein kinase (AMPK), which plays a key role in regulating cellular energy metabolism through phosphorylation, and genetic variations in the PRKAA1 have been found to be associated with gastric cancer risk. However, the effect and underlying molecular mechanism of PRKAA1 on gastric cancer tumorigenesis, especially the proliferation and apoptosis, are not fully understood. Our data showed that PRKAA1 is highly expressed in BGC- 823 and MKN45 cells and is expressed low in SGC-7901 and MGC-803 cells in comparison with the other gastric cancer cells. PRKAA1 downregulation by shRNA or treatment of AMPK inhibitor compound C significantly inhibited proliferation as well as promoted cell cycle arrest and apoptosis of BGC-823 and MKN45 cells. Moreover, the expression of PCNA and Bcl-2 and the activity of JNK1 and Akt signaling were also reduced in BGC-823 and MKN45 cells after PRKAA1 downregulation. In vivo experiments demonstrated that tumor growth in nude mice was significantly inhibited after PRKAA1 silencing. Importantly, inactivation of JNK1 or Akt signaling pathway significantly inhibited PRKAA1 overexpression-induced increased cell proliferation and decreased cell apoptosis in MGC-803 cells. In conclusion, our findings suggest that PRKAA1 increases proliferation and restrains apoptosis of gastric cancer cells through activating JNK1 and Akt pathways.     

miR-145调控肝癌腹水模型Th9细胞升高的机制研究

目的:探讨miR-145调控肝癌腹水模型Th9细胞升高的作用机制。方法:构建小鼠H22肝癌腹水模型。造模两周后处死小鼠并分离出脾脏组织，流式细胞术分析肝癌腹水组（MA组）与正常对照组（Control 组）小鼠脾脏Th9细胞表达水平。ELISA法检测脾脏IL-9表达水平。RT-PCR法检测脾脏miR-145表达水平。Western Blot法检测脾脏中PI3K/Akt/mTOR/P70S6K/HIF-1α相关蛋白表达水平。分选小鼠脾脏CD4+T细胞，随机分为miR-145 mimics组和NC组，分别应用miR-145-5P mimics、阴性对照寡核苷酸（negative control，NC）进行转染，RT-PCR检测各组miR-145、HIF-1α mRNA及IL-9 mRNA表达水平。结果:与Control 组相比，MA组Th9细胞及其细胞因子IL-9表达均升高（P<0.05），miR-145表达降低（P<0.05），p-PI3K、p-Akt、mTOR、p-mTOR、p-P70S6K、HIF-1α蛋白均升高（P<0.05）。与NC组相比，miR-145 mimics组miR-145显著升高，HIF-1α mRNA及IL-9 mRNA表达下降。结论:肝癌腹水中Th9细胞升高可能与miR-145下降导致的PI3K/Akt/mTOR/P70S6K/HIF-1α通路激活有关。     

基于SNP芯片研究PI3K/Akt/mTOR通路上自噬相关基因SNPs与胃癌的关联

目的： 探讨与胃癌发生相关的PI3K/Akt/mTOR通路上新的与自噬相关基因单核苷酸多态性位点（SNPs），为寻找有价值的胃癌发生相关的分子标志物提供新的依据。方法： 采用1：1配对病例-对照研究的方法。通过KEGG pathway网站和Gene Ontology、Ensemble数据库及HaploView、STRING、Cytoscape软件联合SNP芯片筛选目标SNPs，采用基质辅助激光解吸电离飞行时间质谱（MALDI-TOF-MS）对筛检出来的SNPs位点在来自福建省仙游县的622例胃癌患者和622例健康人群基因组中进行验证。结果： SNP芯片及生物信息学分析筛选出IRS1 rs10205233、PIK3CD rs3934934、PIK3R1 rs706711、PIK3R1 rs706714和AKT1 rs35285446为候选位点。扩大样本验证发现IRS1 rs10205233的多态性变异（C > T）显著降低了胃癌的发病风险[共显性模型、显性模型的OR（95% CI）分别为0.761（0.595，0.975）、0.764（0.601，0.973）]。进一步分层分析，该位点显性模型、隐形模型、共显性模型以及等位基因在贲门癌和非贲门癌人群中均未见统计学差异（P > 0.05）。并未见其他位点与患胃癌风险的关联有统计学意义。对PIK3R1基因2个位点（rs706711、rs706714）的单体型分析也未见统计学差异。结论： IRS1 rs10205233位点与福建省胃癌高发区仙游县的胃癌发生存在关联，T等位基因可能是胃癌发生的一个遗传保护因素。